Gaya APA
Longman english course book 4. (2014).
tempaterbit:
penerbit.
Gaya Chicago
Longman english course book 4.
Edisi.
tempaterbit:
penerbit,
2014.
Text.
Gaya MLA
Longman english course book 4.
Edisi.
tempaterbit:
penerbit,
2014.
Text.
Gaya Turabian
Longman english course book 4.
tempaterbit:
penerbit,
2014.
Print.